Kuan-Ling Liu of Ganzin Technology models the Ganzin Aurora eye tracker module, which can be used to control a variety of function using eye movement, at 'CES Unveiled' during the 2019 CES in Las Vegas, Nevada. (Image: Reuters)

A Solar Cow battery charging station for schools, designed to encourage parents in developing nations to send their children to school in exchange for battery power at 'CES Unveiled' during the 2019 CES in Las Vegas. (Image: Reuters)

The Soundbrenner Pulse, the top version is a vibrating metronome, with the newer model also being a watch and a guitar tuner, shown here at the CES Unveiled during the 2019 CES in Las Vegas, Nevada. (Image: Reuters)